macrumors bot

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Interesting.. at least the writer admits several times that due to the nature of his work, he sees failed units and not successfully working ones. But this does worry me a bit. Time to seriously consider AppleCare when my one year is close to being up.

macrumors 6502a

i completely agree with his opinion. at compusa, we took a picture of all the imac g5s that filled our tech shelves at one time, lets just say that we had to take more than one photo. we had at least 15-20 imac at one time because of power supply issues. so there is, in my opinion as well, a flaw in the design. just make sure you have applecare i guess

macrumors G3

The iSlabs have been unusually prone to premature death, haven't they? Other models have their trademark problems too, but usually they're more in the annoyance category than the bursting into flames one.

macrumors 68040

On a tangentially related note... this article uses "could of," which is not a valid English structure, but a roughly phonetic (but incorrect) spelling of "could've," which of course is short for "could have." "Could of" doesn't mean anything. Please be on the lookout for this problem in your own writing, as I've noticed it has become more and more common.

macrumors 6502a

it would be interesting to know what the actual numbers are... i've used just about every mac in the last 20 or so years and never once had a hardware problem. that is till the 20" imac. first my hard drive was replaced, then the logic board and power supply, and on the third go around with new hard drive problems, my imac was replaced with a second gen... let's hope new intel chips will keep things a little cooler and help out with the hardware issues in the future.

macrumors 6502a

I have read about imac G5 reliability issues elsewhere as well. There is an apparent flaw in how the imac's cooling system functions. I have a friend who had two Hard drives fail and this was in a second generation imac as well. Barefeats.com has an article about overheating imac hard drives and how to make a heatsink.

Remember water will usually boil at 100C/212F and this imac was almost there at 89C/192F!! To put the imac temperature issue into perspective nothing in my Dual 2.5Ghz PowerMac G5 reaches over 176F even under full load. My Hard drive never goes above 100F ambient temp and the memory controller heat sink is the hottest thing in my PowerMac but never exceends 176F.

Aparently premature Hard Drive failure occurs quite often in the imac G5 even if your machine's HD is not running near boiling temperatures it is probably running hotter than the drive manufacturer specifies or pretty darn close to maximum operating temp. Of course Hard Drives can be easily replaced bursting capacitors, smoking GPU's and fried motherboards sound much more disturbing.

macrumors regular

Macintouch has quite a few tales of this sort, as have some other sites. It has baffled me why there hasn't been more on MacRumors or MacBytes about it until now.

IIRC, heat-related issues are what delayed the iMac G5 intro a year ago. Guess they didn't get 'em all fixed after all.

A dirty shame. It's a beautiful piece of work. Perhaps in the not-too-distant future Apple will intro a similar form factor with a (let us hope) cooler-running Intel CPU. Until then, iMac G5 will be too big a risk for many. AppleCare notwithstanding, who wants the hassle? Who wants the burned plastic smell? For that matter, who wants the fire hazard?

macrumors 6502a

Macintouch has quite a few tales of this sort, as have some other sites. It has baffled me why there hasn't been more on MacRumors or MacBytes about it until now.

IIRC, heat-related issues are what delayed the iMac G5 intro a year ago. Guess they didn't get 'em all fixed after all.

A dirty shame. It's a beautiful piece of work. Perhaps in the not-too-distant future Apple will intro a similar form factor with a (let us hope) cooler-running Intel CPU. Until then, iMac G5 will be too big a risk for many. AppleCare notwithstanding, who wants the hassle? Who wants the burned plastic smell? For that matter, who wants the fire hazard?

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I don't think that the IBM PowerPC 970FX is to blame for the excessive heat. It is not the processor that is overheating but components on the motherboard like those huge capacitors or even GPUs and oddly Hard Drives.

If Apple can stick two 2.3Ghz PowerPC 970s in the Xserve sub 2 inch thick form factor without these kind of problems it is deffinitely something else that is causing the overheating. imacs with even 1.8Ghz and some 1.6Ghz G5 units have had overheating issues. The overheating is clearly an overall case of a bad cooling implementation that is inadequate for the islab form factor. If it were the G5 processors I assume Apple could always switch to the newly announced low power G5s assuming that they will be available shortly to tide us over until we switch to an intel based imac sometime mid next year.

macrumors 6502

On a tangentially related note... this article uses "could of," which is not a valid English structure, but a roughly phonetic (but incorrect) spelling of "could've," which of course is short for "could have." "Could of" doesn't mean anything. Please be on the lookout for this problem in your own writing, as I've noticed it has become more and more common.

macrumors regular

If Apple can stick two 2.3Ghz PowerPC 970s in the Xserve sub 2 inch thick form factor without these kind of problems it is deffinitely something else that is causing the overheating.

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I don't really agree to that... Technically you are right of course but then again the XServe has two huge fans. I don't know the XServe from experience but I do know XServe RAID and that thing has it's fans always on. And since those are Server products customers don't care because the units are normaly tucked away in a server room anyway.

I don't get why they don't use small heatsinks on the HD and other components that are as of now "unprotected". The "windtunnel" approach from the MDD G4, the newer PowerBooks or the G5 PowerMacs would also help I assume.

Or why not a Software Update in the first place? Lower the temperature threshold... Better a loud Mac than a dead Mac...

macrumors 68000

I don't think that the IBM PowerPC 970FX is to blame for the excessive heat. It is not the processor that is overheating but components on the motherboard like those huge capacitors or even GPUs and oddly Hard Drives.

If Apple can stick two 2.3Ghz PowerPC 970s in the Xserve sub 2 inch thick form factor without these kind of problems it is deffinitely something else that is causing the overheating. imacs with even 1.8Ghz and some 1.6Ghz G5 units have had overheating issues. The overheating is clearly an overall case of a bad cooling implementation that is inadequate for the islab form factor. If it were the G5 processors I assume Apple could always switch to the newly announced low power G5s assuming that they will be available shortly to tide us over until we switch to an intel based imac sometime mid next year.

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Well the xServe G5 has 7 little tiny fans, and also 2 blowers so its a lot easier to cool it. Plus, there's a separate heat sink on the system controller and its a longer than an iMac so there's more room to move air around in. So really, an xServe is a helluva lot easier to cool than an iMac G5.

macrumors regular

The issues are not related to heat at all. There was a batch of bad capacitors used by a subcontractor. The caps are failing over time. The replacement parts are not subject to the same issue and should last the expected life of the machine (generally the life span of the lights in the LCD panel).
There is no fundamental design flaw in the iMac G5 and they are not overheating.

macrumors 65816

There is no fundamental design flaw in the iMac G5 and they are not overheating.

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I think you couldn't be more wrong. Sorry, but there is little to no cooling in that machine. You seriously need to look at it, just a tiny slot on the top and bottom. It needs larger slots and larger fans that turn on at lower temps.

macrumors newbie

I placed an order for a new iMac 20" prior to the actual release date and thus, of course, have one of the earliest models.

Now less than a year later, the 160GB hard drive (with all my photos and videos) has died and when I brought it into the Apple store, the logic board had bulging capacitors... In essense, the major components have failed outright.

In 15 years of computers (both WinTel and Mac), I've never had a computer so comprehensively fail. I accept that these things happen and perhaps I was even 'due' given that none of my systems have ever had a hard drive die, much less suffer from bulging capacitors.

I have no intention of switching back to WinTel, but this does make me rethink ever buying a consumer-level Apple computer again.

macrumors 68040

Our store has seen a lot of iMac G5's coming in for repair, they usually share these two problems. Either the screen scrambles, or the machine is completly dead. In the last two months we must have had 15-20 iMac G5s in for repair, this is more then the number of G5s and older iMac G4s or G3s.

macrumors 6502

On a tangentially related note... this article uses "could of," which is not a valid English structure, but a roughly phonetic (but incorrect) spelling of "could've," which of course is short for "could have." "Could of" doesn't mean anything. Please be on the lookout for this problem in your own writing, as I've noticed it has become more and more common.

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What about something even worse..

dog's, cat's, and Mac's are cool.

gr............apostrophes are for making something possesive...not pluralisation.

macrumors 603

Will you guys consider the iMac G5 as bad as the logic board problem with the ibook G3's? I am happy rev b's have been more reliable then rev a's which is expected. My 20" iMac G5 2 Ghz with the 250 GB HD has been quietly humming along. With the CPU under normal use hovering in between 125-145 F. Mostly in the 129's and 136's. The HD temp is consistent at 122 F. Under full load via playing X-Plane the CPU have gotten to 186 max from what I have seen. I can hear the fans, but not that much.

macrumors 68000

We bought an iMac G5 20" this May. It does not seem to be running especially warm. The fan only comes on if we leave it sitting with certain games running for a long time. No problems so far but because of the history of problems with the previous generation of iMac G5's we did spring for the AppleCare.

macrumors 6502a

If Apple can stick two 2.3Ghz PowerPC 970s in the Xserve sub 2 inch thick form factor without these kind of problems it is deffinitely something else that is causing the overheating.

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Well, okay, but let's not forget that one of those systems costs $3000 for specs that (dual procs notwithstanding) are not even up to the level of a $1500 iMac. There's a lot less corner-cutting in the Xserves.

macrumors regular

I think you couldn't be more wrong. Sorry, but there is little to no cooling in that machine. You seriously need to look at it, just a tiny slot on the top and bottom. It needs larger slots and larger fans that turn on at lower temps.

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*sigh*
l look at them every day, it's what I do for a living. If you actually looked at them and understood what was going on in the case you'd see there is quite a lot of cooling in the machine. First, the entire case is laid out to take advantage of convection. Even without the blowers cool air would go in the bottom and hot air exhaust out the top. The entire rear case has a heavy metal heat sink that spreads and radiates heat out the back panel.
Aside from that design, there is a dedicated CPU blower, a dedicated HD blower and a general case blower. The CPU has a dedicated intake and exhaust path. The case and HD blowers both draw air in from through the power supply and exhaust it out the side behind the optical drive.
All of the blowers are on all the time but the speed changes according to workload and ambient temperatures. In a "normal" room at 72-75F the blowers are usually at or near idle. At 85F the blowers spin up significantly and are easily audible at normal operating distances. Who's sitting in front of a computer in an 85 degree room? I don't know.
I've not actually looked at the numbers but I'd not be surprised if the 2.0Ghz CPU in an iMac actually ran cooler than the 2.0GHz CPUs in a Powermac.

macrumors 65816

I've not actually looked at the numbers but I'd not be surprised if the 2.0Ghz CPU in an iMac actually ran cooler than the 2.0GHz CPUs in a Powermac.

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Wow, that was actually really informative. Thanks. Apparently I knew less than I thought. But I don't think they run cooler than the PMs, because several people have posted iMac numbers and PM numbers and the iMacs were around 150-170F and the PM were around 130F. On that same note, I've heard of iMacs running at 130 also. It seems there we are a good chunk of lemons or something.

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